{
  "abstract": "Background and Aims The Midclavicle Block combines the clavipectoral fascia plane block with a targeted injection into the subclavius muscle to enhance anesthetic spread. Objective: To evaluate the anatomical distribution pattern of the Midclavicle Block in cadaveric specimens with midshaft clavicle fractures, with a focus on periosteal coverage and involvement of the fracture site.Methods An anatomical study was conducted on ten cadavers (twenty clavicular regions). A midshaft clavicle fracture model was created, and the MCB technique was applied under ultrasound guidance. A methylene blue solution was injected, and dissections were performed to evaluate dye spread primarily in the deep muscular and the clavicular plane, including the fracture site. Probabilistic maps of dye distribution were generated.Results The anatomical dissection in the deep muscular plane revealed consistent staining of the fracture site in all specimens, along with the subclavius muscle and the clavipectoral fascia, while the pectoralis minor muscle remained unaffected in every case ( figure 1). As the dissection progressed toward the infraclavicular brachial plexus plane, no staining of the plexus was observed, with dye spread restricted to the subclavius muscle and adjacent clavipectoral fascia (figure 2). The mean staining of the anterosuperior and posteroinferior periosteal surfaces was 55.3% ± 10.4 and 54.2% ± 9.0, respectively (figure 3). The highest dye concentration was observed in the middle third of the clavicle, corresponding to the fracture zone.Abstract EP009 Figure 1Anatomical dissection of the deep muscular plane, clavicular plane, and fracture site. Methylene blue was injected deep to the subclavius muscle. Stained structures include the clavicular periosteum and the fracture site (1), as well as the clavipectoral fascia (2). The pectoralis minor muscle (3) remains unstained, suggesting that the clavipectoral fascia acts as an anatomical barrier to dye spread. The magnified view confirms consistent staining at the fracture siteAbstract EP009 Figure 2Anatomical dissection showing the distribution of methylene blue in the clavicular plane at the level of the brachial plexus. Stained structures include the clavicular periosteum and fracture site (1), the subclavius muscle and clavipectoral fascia (2), while the pectoralis minor (3) remains unstained. The brachial plexus (4) shows no evidence of dye spread following application of the Midclavicle Block techniqueAbstract EP009 Figure 3(A) Dissection of the clavicular periosteum showing methylene blue staining on both the anterosuperior and posteroinferior surfaces of the clavicle; (B) Probabilistic heatmap illustrating the percentage of stained area across the same regions, presented in anterosuperior and posteroinferior views. The color gradient represents staining intensity, ranging from 0% (black) to 100% (red)Conclusions The Midclavicle Block resulted in effective periosteal coverage and targeted fracture site staining. Clinical studies are needed to confirm its in vivo efficacy, given the limitations inherent to cadaveric specimens.",
  "authors": [
    {
      "affiliations": [
        "Laboratory of Surgical Neuroanatomy (LSNA). Human Anatomy and Embryology Unit, Faculty of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain"
      ],
      "name": "Hipolito Labandeyra"
    },
    {
      "affiliations": [
        "Laboratory of Surgical Neuroanatomy (LSNA). Human Anatomy and Embryology Unit, Faculty of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain"
      ],
      "name": "Xavier Sala-Blanch"
    },
    {
      "affiliations": [
        "Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota, USA"
      ],
      "name": "Ryan D’Souza"
    },
    {
      "affiliations": [
        "Anesthesiology, Hospital Costa del Sol, Marbella, Spain"
      ],
      "name": "Luis Váldes-Vilches"
    },
    {
      "affiliations": [
        "Laboratory of Surgical Neuroanatomy (LSNA). Human Anatomy and Embryology Unit, Faculty of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain"
      ],
      "name": "Alberto Prats-Galino"
    }
  ],
  "title": "EP009 Midclavicle block for midshaft clavicle fractures: an anatomical study",
  "uid": "e32f8017-2f58-5f1f-b139-3dac233e5597"
}